till和until一般情況下兩者可以互換,但是在強(qiáng)調(diào)句型中多用until.并且要注意的是：如果主句中的謂語動(dòng)詞是瞬時(shí)動(dòng)詞時(shí),必須用否定形式；如果主句中的謂語動(dòng)詞是延續(xù)性動(dòng)詞時(shí),用肯定或否定形式都可以,但表達(dá)的意思不同.例如：
I didn't go to bed until（till） my father came back.直到我父親回來我才上床睡覺.
It was not until the meeting was over that he began to teach me English.直到散會(huì)之后他才開始教我英語.
I worked until he came back.我工作到他回來為止.
I didn't work until he came back.他回來我這才開始工作.
Please wait until I arrived.在我到達(dá)之前請(qǐng)等我.